/*
Given an absolute path for a file (Unix-style), simplify it.

For example,
path = "/home/", => "/home"
path = "/a/./b/../../c/", => "/c"
click to show corner cases.

Corner Cases:
Did you consider the case where path = "/../"?
In this case, you should return "/".
Another corner case is the path might contain multiple slashes '/' together, such as "/home//foo/".
In this case, you should ignore redundant slashes and return "/home/foo".
*/

class Solution {
public:
    string simplifyPath(string path) {
        vector<string> dirs;
        for (auto i = path.begin(), j = path.end(); i != path.end(); i=j) {
            i++; j = find(i, path.end(), '/');
            string str = string(i,j);
            if (str.empty() || str == ".") { continue; }
            else if (str == "..") { if (!dirs.empty()) dirs.pop_back();} 
            else dirs.push_back(str);
        }
        string output;
        if (dirs.empty()) {
            output = "/";   // root dir
        } else {
            for (auto it = dirs.begin(); it != dirs.end(); it++) {
                output.append(1, '/'); output.append(*it);
            }
        }
        return output;
    }
};
